He goes from baseball and Boy Scouts to black gothic clothes and nail polish, from studying for a merit badge to poring over the “Satanist’s Bible.”

Parents of teenagers surely shuddered at the news of Scott Dyleski, the 16-year-old Lafayette boy accused in the savage beating death of a neighbor, the wife of a prominent lawyer and television commentator. After all, boys and girls sharing Dyleski’s “goth” taste for medieval attire and morbid music can be found in just about any high school.

Does it signal simmering rage waiting to erupt in lethal violence, or just a harmless expression of individuality and creativity? Experts in teen psychology and juvenile crime say parents should resist fretting over their kids’ wardrobes and musical tastes. What matters more is whether they have healthy relationships with their family and friends.

Dyleski had suffered through ugly court battles between his divorcing parents and more recently, the death of his half-sister in a car crash. Still, it doesn’t necessarily follow that family tragedies spawn teen violence.

Taking a break?

“In and of itself is that going to trigger people to become violent? No,” Wolf said. “But obviously it’s a big source of stress. It can increase chances that something further bad can happen.”

Shortly after his sister’s 2002 death, classmates said Dyleski started wearing dark clothes, became more withdrawn and adopted a “goth” style popularized by shock-rocker Marilyn Manson. Goths, who often view themselves as outcasts, have been eyed with suspicion ever since two trench-coat clad teens at Columbine High School in Colorado massacred 12 classmates and a teacher in a 1999 rampage that ended in their suicides.

A person familiar with the family said it wasn’t surprising that Dyleski adopted the “goth” style in the eighth grade. Dyleski’s classmates at both middle school and high school were generally kids from well-off families living in affluent Lafayette. Dyleski and his mother had spent time camping in a lean-to on the property where they eventually moved into a house built by his mother’s friends, where they lived in a sort of communal fashion.

“My opinion was always that he didn’t fit in, so he made a point of not fitting in,” said the person who asked to remain anonymous.

“It’s not about what they’re wearing, it’s about what they’re doing,” said Don Elium, a marriage and family therapist in Walnut Creek and co-author of the 1992 book, “Raising a Son: Parents and the Making of a Healthy Man,” which was revised last year.

Elium said warning signs of a dangerously troubled teenager include a pattern of lying to parents, failing to keep commitments with them, and secretiveness about who their friends are and where they go with them.

“The number one concern — are they keeping their commitments with you, do they do the chores they say they are going to do, come in when they say they will?” Elium said. “Second is who do they hang out with and where? If you don’t know, that’s a red flag.”

“If a kid suddenly changes to dressing in black, is that a reason in and of itself to take my child off to see some kind of psychologist? The answer is no,” Wolf said. “On the other hand, it makes me be at least a little more vigilant, to think, are there other things going on in my kid’s life? A lot of the kids who dress in goth style are genuinely really good kids. Sometimes, what that means is that you never really got into football.”

Wolf said that rather than looking for a checklist of danger signs, parents should trust their instincts.

“It’s much better to err on the side of caution,” Wolf said. “If you’re worried about it, I’d try to enlist the help of a professional.”

Dyleski’s parents could not be reached for comment. But the person familiar with his family said she believed the teenager never received any counseling after his sister died.

Mike A. Males, senior research fellow at the Center on Juvenile and Criminal Justice in San Francisco and a UC Santa Cruz sociology professor, agrees that outside of obvious violent threats or behavior, warning signs aren’t always apparent, even to professionals.

“There’s too much guilt placed on people that they should have seen it coming,” Males said. “This isn’t easy. Psychologists with years of training cannot see these things coming.”

But Males urges parents to keep things in perspective, and warns of the dangers of overreacting.

“The comforting thing is something like this is extremely rare,” Males said. “There’s been a tremendous over-commitment of teenagers to psychiatric facilities, over-medication, based on this fear that there’s this weird teenage scourge out there. We’ve made this pathology about teenagers. Ninety-nine percent of teenagers who have traumatic experiences, who put black eyeliner on, who get into extreme sports, don’t commit murders.”

The Mercury News strives to avoid use of unnamed sources. When unnamed sources are used because information cannot otherwise be obtained, the newspaper generally requires more than one source to confirm the information.